Water - 4.1 Water quality

Poor quality water can transfer contaminants to livestock, poultry and food.

This good agricultural practice applies to all farms.

What needs to be done

Reduce food safety hazards associated with contaminated water by ensuring water quality is suitable for its intended use.

How to do it

Assess the water source

Water quality for agricultural use varies depending on the:

1. Water source (for example a river, stream, pond, ditch, lake, well, dugout or municipal)
2. Usage of the water, (for example irrigation, crop washing, cleaning and sanitation procedures, or for livestock)

Water quality is a term used to describe the chemical, physical, and biological characteristics of water, usually in respect to its intended use.

Potable water means water provided by a domestic water system that meets the standards prescribed by regulation, and is safe to drink and fit for domestic purposes without further treatment.

Grey water is domestic wastewater that has been used to clean food or food contact surfaces. This used water is considered unfit for human to drink but may be recycled for an agricultural purpose that does not require potable water, such as washing a barn floor. Recycling this used water lowers the need for fresh water and puts less strain on an on-site septic system.

Wastewater contains both nutrients (for example, manure) and harmful contaminants, of which many are invisible. Contaminates of concern are:

• Pathogenic microbes like viruses, bacteria and parasites which can make both humans and animals sick
• Chemical contaminants from pesticides, petroleum-based products, heavy metals, and leachates. These are usually picked up by run-off water from a farm site

Disposal of wastewater must follow both environmental and health legislation guidelines to ensure that wastewater is handled in a way that protects other water sources, humans, and aquatic life.

Assess the intended use

Cleaning and sanitizing

Use potable water when cleaning and sanitizing food contact surfaces and for hand washing facilities.

Crops

For final washing, cooling and ice making use potable water (for example, the water complies with Canadian drinking water quality standards).

Canadian drinking water standards are:

• E. coli: not detected in 100 mL water
• Total coliforms: not detected in 100 mL water.  (Total coliforms include bacteria that are found in the soil, in water that has been influenced by surface water, and in human or animal waste.)

* Source: Health Canada, 2002. Guidelines for Canadian Drinking Water Quality – Summary Table.

For irrigation of crops eaten raw, use water that complies with the B.C. Ministry of Environment and Health Canada standards: 

• E. coli: <77 bacteria in 100 mL water
• Fecal coliforms: <200 bacteria in 100 mL water

* Source: B.C. Ministry of Agriculture and Land, 2003. Treating Irrigation and Crop Wash Water for Pathogens. Factsheet #512.000-3.

For general irrigation, use water that complies with the Canadian water quality guidelines for the protection of agricultural water uses:  Total coliforms: <1,000 bacteria in 100 mL water

* Source: Environment Canada, 2002. Canadian Water Quality Guidelines for the Protection of Agricultural Water Uses.

Livestock

There are no definite guidelines for the presence of microbes in livestock drinking water sources. Suggestions are total bacteria: <10,000 per 100 mL, some reports suggest that total coliforms need only be <5,000 per 100 mL.

* Source: Agriculture and Agri-Food Canada, Prairie Farm Rehabilitation Administration

Canadian Water Quality Guidelines also have recommendations for heavy metals and pesticides levels for livestock drinking water.

Testing water quality

Test water at the point of use ( for example, out of a tap, irrigation line), not at the source, because water can become contaminated by the time it reaches the point of use.

To test water for bacteria counts, contact an accredited laboratory. Here is a list of laboratories approved by BC Provincial Health Officer. (Provincial Health Authority).

Water should be tested at least once a year. Frequency of water testing is dependent on water source and intended use.

Interpret the results

When required, seek technical advice from various water, health and agricultural specialists

When the results show a potential food safety hazard exists, stop using the water immediately. This source of water should not be used until it is properly treated and additional results confirm that the hazard no longer exists.

When water quality does not meet the requirements for the intended use, either treat water or find an alternate source.

Protect water sources

Be aware of sources of potential water contamination, such as upstream livestock, run-off, storm sewer overflows, or backflow of irrigation systems. Backflow prevention requirements are described in the ministry publication “Chemigation Guidelines for British Columbia”. The Ministry of Agriculture and Food's Irrigation page and the B.C. environmental farm plan reference guide can provide guidance to protect water sources and preserve water quality. See the “Useful references” section for more information.

Records to keep

Lab-test results for water quality.

If you have an audit

Be prepared for the auditor to:

• Review water quality lab-test results
• Review the frequency established for water testing
• Observe measures to protect water sources and preserve water quality

Laws and regulations 

There are not many specific laws that regulate the water quality to be used in agricultural production for food safety purposes. Generally, water quality in privately owned water systems for individuals is not specifically regulated by either the provincial or federal government, and individuals are responsible for ensuring their water is of good quality. However, requirements for very specific water quality standards are set out in laws regarding the processing of meat, fish and other food products, including egg-stations, as well as other services that deal with the public, which are outside the scope of this page.

Health Canada’s Guidelines for Canadian drinking water quality and the provincial Ministry of Environment’s British Columbia approved water quality guidelines set out the requirements for testing and for maximum allowable levels of specified microbes or chemicals in water that will be consumed by humans.

A specific guideline for agricultural water uses sets out maximum allowable levels for specified microbes or chemicals for irrigation water and livestock water. These are based on crop sensitivity and/or food safety concerns, such as concerns about certain toxic chemicals that may bioaccumulate in animals or about the presence of coliforms. See Canadian Water Quality Guidelines for the Protection of Agricultural Water Uses: Summary Table., updated October 2005. Note that these are guidelines and not legal standards. Check with your local health inspector for water quality standards applicable to your agricultural operation.

Milk Industry Standards Regulation, Reg. 464/81, s. 24 under the Milk Industry Act sets out requirements for milking parlours and milking rooms to have water under pressure for cleaning purposes. S. 31 specifies milk houses shall have an adequate supply of hot and cold water for maintaining the standards of cleanliness.

The Drinking Water Protection Act, S.B.C. 2001, c. 9 and Drinking Water Protection Regulation, Reg. 200/03 set out requirements for domestic water systems in BC. S. 16 (1) of the Drinking Water Protection Act, Drinking Water Protection Regulation, s. 14, Water Act, R.S.B.C. 1996, c. 483, s. 79 (1), and Ground Water Protection Regulation, Reg. 299/2004, s. 11 (1) (2) require the owner of a drinking water system that includes a well used as a raw water supply to ensure that the well is constructed and maintained to prevent surface water and other foreign materials from entering the well.

Producers who use surface or ground water on their farms for irrigation, drinking water for livestock, wash water, cooling water or other purposes should ensure that their farm practices comply with requirements in the Environmental Management Act; Integrated Pest Management Act; Water Act; and Drinking Water Protection Act to prevent contamination of water supplies by pesticides, manure runoff, wash water contamination or other sources of chemical or biological hazards. Note that under the BC Water Act, s. 94 (1)(e) it is an offence to discharge any material into any well that may impair the quality of the ground water.

Canada Agricultural Products Act, Fresh Fruit and Vegetable Regulations (C.R.C., c. 285) Part I.1 s. 3.1 (4) (b) states that only potable water is to be used in the final rinsing of the produce to remove any surface contaminant before packing. S. 3.1 (4) (c) states that the final rinse water, if reused, is used only in the initial washing or fluming of the produce.